SpringMVC异常全局捕获与错误响应的处理方法

package org.example.springmvc.controller;
import org.example.springmvc.common.R;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class helloController {
    @GetMapping(value = "/hello")
    public R hello() {
        // 编程式的异常处理
        try {
            int i = 1 / 0;
            return R.ok(i);
        } catch (Exception e) {
            return R.error(100, "执行异常");
        }
    }
}

package org.example.springmvc.controller;
import org.example.springmvc.common.R;
import org.springframework.web.bind.annotation.*;
@RestController
public class HelloController {
    @GetMapping(value = "/hello")
    public R hello(@RequestParam(value = "i", defaultValue = "0") Integer i) {
        int j = 1 / i;
        return R.ok(j);
    }
    /**
     * 如果Controller本类出现异常，会自动在本类中寻找有没有@ExceptionHandler注解的方法，如果有，则执行
     * 可以根据需求添加多个@ExceptionHandler注解的方法
     * .@ExceptionHandler注解接收多个参数，表示可以拦截多个异常类型
     *
     */
    @ExceptionHandler(ArithmeticException.class)
    public R handleArithmeticException(ArithmeticException e) {
        return R.error(100, "是执行异常" + e.getMessage());
    }
    @ExceptionHandler(Exception.class)
    public R handleException(Exception e) {
        return R.error(200, "异常" + e.getMessage());
    }
}

package org.example.springmvc.advice;
import org.example.springmvc.common.R;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
//@ResponseBody
//@ControllerAdvice
@RestControllerAdvice//合成注解
public class GlobalExceptionHandler {
    @ExceptionHandler(ArithmeticException.class)
    public R handleArithmeticException(ArithmeticException e) {
        return R.error(100, "是执行异常" + e.getMessage());
    }
    @ExceptionHandler(Exception.class)
    public R handleException(Exception e) {
        return R.error(200, "异常" + e.getMessage());
    }
}

throw new BizException(BizExceptionEnum.ORDER_NOT_EXIST);

package org.example.springmvc.exception;
public enum BizExceptionEnum {
    //ORDER订单模块
    ORDER_NOT_EXIST(10001, "订单不存在"),
    ORDER_STATUS_ERROR(10002, "订单状态错误"),
    ORDER_PAID(10003, "订单已支付"),
    ORDER_CANCEL_FAIL(10004, "订单取消失败"),
    ORDER_PAY_FAIL(10005, "订单支付失败"),
    //PRODUCT商品模块
    PRODUCT_STOCK_NOT_ENOUGH(20001, "商品库存不足"),
    PRODUCT_OFF_SALE_OR_DELETE(20002, "商品下架或删除"),
    PRODUCT_NOT_EXIST(20003, "商品不存在"),
    PRODUCT_STOCK_ERROR(20004, "商品库存有误"),
    //USER用户模块
    USER_NOT_EXIST(30001, "用户不存在"),
    USER_PASSWORD_ERROR(30002, "密码错误"),
    USER_ACCOUNT_ERROR(30003, "账号错误"),
    USER_ACCOUNT_LOCK(30004, "账号已被锁定"),
    USER_LOGIN_FAIL(30005, "用户名或密码错误"),
    USER_ACCOUNT_FORBIDDEN(30006, "账号已被禁用"),
    //OTHER其他模块
    OTHER_ERROR(40001, "其他错误"),
    ;
    private final int code;
    private final String msg;
    BizExceptionEnum(int code, String msg) {
        this.code = code;
        this.msg = msg;
    }
    public int getCode() {
        return code;
    }
    public String getMsg() {
        return msg;
    }
}

package org.example.springmvc.exception;
public class BizException extends RuntimeException{
    //业务异常码，业务异常原因
    private final Integer code;
    private final String msg;
    public BizException(Integer code, String msg) {
        super(msg);
        this.code = code;
        this.msg = msg;
    }
    //Controller感知异常，被全局异常处理器捕获，然后调用异常对象的构造方法，将异常码和异常原因传递给异常对象，
    //通过这个构造方法，可以将BizExceptionEnum枚举对象 传给 BizException，然后抛出异常
    public BizException(BizExceptionEnum bizExceptionEnum) {
        super(bizExceptionEnum.getMsg());
        this.code = bizExceptionEnum.getCode();
        this.msg = bizExceptionEnum.getMsg();
    }
    public Integer getCode() {
        return code;
    }
    public String getMsg() {
        return msg;
    }
}

package org.example.springmvc.advice;
import org.example.springmvc.common.R;
import org.example.springmvc.exception.BizException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
//@ResponseBody
//@ControllerAdvice
@RestControllerAdvice//合成注解
public class GlobalExceptionHandler {
    @ExceptionHandler(ArithmeticException.class)
    public R handleArithmeticException(ArithmeticException e) {
        return R.error(100, "是执行异常" + e.getMessage());
    }
    @ExceptionHandler(BizException.class)//这里传递的e已经提前封装好了
    public R HandleBizException(BizException e) {
        return R.error(e.getCode(), e.getMsg());
    }
    @ExceptionHandler(Throwable.class)
    public R handleThrowable(Throwable e) {
        return R.error(500, "异常" + e.getMessage());
    }
}